Nine students were hospitalized after getting maced by a classmate at a school in Harlem this afternoon, according to authorities.

The students from the Academy for Social Action: A College Board School — which serves grades 6 to 12 — were taken to nearby St. Luke’s-Roosevelt hospital with minor injuries.

Officials said a 14-year-old girl released mace into an occupied fourth floor classroom at the building on West 129th street shortly after 2:30 p.m. One student said the girl had reportedly sprayed the irritant indiscriminately into the air.

A Department of Education spokeswoman said cops issued the 14-year-old a juvenile report and that officials are investigating.

Self-defense sprays have been making headlines across the country lately — from complaints of police tactics against protesters in New York City and the University of California, Davis, to its use by a Walmart shopper in California during a Black Friday scrum.

Academy for Social Action principal Rhokeisha Ford did not immediately respond to a request for comment.